Use the equation d=m/v
your mass or "m" is 78 g
your volume or "v" is 60mL
if you plug those values into the equation it will look like this:
d=78/60
d=1.3g/mL should be what you come up with
Answer: The one listed below that's NOT an example of potential energy is mechanical energy. Mechanical energy is categorized as a kinetic energy with light, sound, and thermal/heat energy.
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Moles are the division of the mass and the molar mass. The moles of mercury (ii) oxide in the decomposition reaction needed to produce oxygen are 0.781 moles.
<h3>What is a decomposition reaction?</h3>
A decomposition reaction is a breakdown of the reactant into simpler products. The decomposition of mercury (ii) oxide can be shown as:
2HgO(s) → 2Hg(l) + O₂(g)
From the reaction, it can be said that 2 moles of mercury (ii) oxide decomposes to produce 1 mole of oxygen.
The moles of oxygen that needs to be produced are calculated as:
Moles = mass ÷ molar mass
= 12.5 gm ÷ 32 gm/mol
= 0.39 moles
0.39 moles of oxygen are needed to be produced.
From the stoichiometric coefficient of the reaction, the moles of HgO is calculated as: 2 × 0.39 = 0.781 moles
Therefore, 0.781 moles of HgO are required in the reaction.
Learn more about moles here:
brainly.com/question/3801333
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